I'm just not getting this: I'm sorry, I'm still back on this point. But, suppose I want to measure sensor sharpness. Why, I don't know, but this thread is about sensor sharpness.
Strange. I thought it was about format sharpness, of which the abstract dimensionless notion of sensor sharpness is just one rather insignificant part.
Perhaps if you could explain what you mean by the difference between a sharp sensor as opposed to a sharp camera we could make some progress.
Is a sharp sensor something that makes the sharpest images of newspapers taped to a wall, doing whatever you need to to maximize the sharpness of said newspaper?
If so...who cares? Why would you not be more interested in how sharp the camera system as a whole is when used the way cameras are actually used?
Let's say you rubbed a lamp and got three wishes and used one of them for the sharpest sensor in the world. But the trickster genie gave you a sensor that only produced sharp images when used at a distance of 1" from its subject. What good would that do you?
Unless, of course, all you do is photograph newspapers taped to walls...in which case, I gotta tell you, there are much better ways to make sharp images of a newspaper than by taping it to a wall and photographing it with a camera....
Right, so why would you change lenses?